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手性氨基醇催化的前手性芳酮的不对称还原反应

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有机化学 2005年第6期25卷 669-672页

作者：程青芳许兴友杨绪杰尤田耙淮海工学院化工系连云港222005 南京理工大学材料化学实验室南京210094 中国科学技术大学化学系合肥230026

首次以天然D-樟脑的衍生物为原料,合成了两个新型龙脑基氨基醇配体,研究了它们与硼烷原位制备成手性噁唑硼烷后,在不对称催化氢化还原前手性芳酮中的性能,得到的手性仲醇的对映体过量(ee)值最高可达96%,还考察了反应温度、时间、溶剂等... 详细信息

首次以天然D-樟脑的衍生物为原料,合成了两个新型龙脑基氨基醇配体,研究了它们与硼烷原位制备成手性噁唑硼烷后,在不对称催化氢化还原前手性芳酮中的性能,得到的手性仲醇的对映体过量(ee)值最高可达96%,还考察了反应温度、时间、溶剂等因素对苯乙酮的不对称氢化还原的化学产率和光学收率的影响.

关键词：前手性芳酮不对称还原反应手性氨基醇手性噁唑硼烷氢化还原不对称催化对映体过量原位制备手性仲醇反应温度化学产率衍生物苯乙酮配体龙脑时间光学

龙脑基β-二酮铁配合物催化的苯乙烯类化合物的不对称环氧化反应

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化学学报 2006年第18期64卷 1916-1920页

作者：程青芳许兴友李树安沙鸥杨绪杰尤田耙淮海工学院化工系连云港222005 南京理工大学材料化学实验室南京210094 中国科学技术大学化学系合肥230026

合成了四个龙脑基β-二酮Fe(III)络合物,并用它来催化苯乙烯类化合物在氧气和2-乙基丁醛作用下的不对称环氧化反应.在25～30℃下,反应获得较高的化学产率,得到的手性环氧化合物的ee范围为47.5%～91.6%.考察了催化剂结构、底物结构、反... 详细信息

合成了四个龙脑基β-二酮Fe(III)络合物,并用它来催化苯乙烯类化合物在氧气和2-乙基丁醛作用下的不对称环氧化反应.在25～30℃下,反应获得较高的化学产率,得到的手性环氧化合物的ee范围为47.5%～91.6%.考察了催化剂结构、底物结构、反应温度等因素对反应的化学产率和光学收率的影响.

关键词：不对称环氧化苯乙烯龙脑基β-二酮 Fe(Ⅲ)络合物

A New Compound from the Bud of Chrysanthemum indicum L.

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Chinese Chemical Letters 2005年第10期16卷 1341-1342页

作者： Wen Ming CHENG tian pa you Jun LI Department of Chemistry University of Science and Technology of China Hefei 230026 School of Pharmacy Anhui Medical University Hefei 230032

A new bicyclic spiroketone was isolated from the bud of Chrysanthemum indicum L. The chemical structure was elucidated as （1R, 9S, 10S）-10-hydroxyl-8 （2＇, 4＇-diynehexylidene）- 9-isovaleryloxy-2, 7-dioxaspiro [5,... 详细信息

关键词： Chrysanthemum indicum L. X-ray crystallography bicyclic spiroketone (1R 9S,10S)-10-hydroxyl-8 (2' 4'-diynehexylidene)-9-isovaleryloxy-2 7-dioxaspiro[5 4]decane.

Asymmetric Cyclopropanation Catalyzed by Four Stereoisomers of a Copper-(Schiff-base) Complex with Double Chiral Centers

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Chinese Chemical Letters 2002年第12期13卷 1143-1146页

作者： Chang Sheng JIANG you Gui LI Chen JIANG Fang WANG tian pa you Department of Chemistry Universtity of Science&Technology of ChinaHefei 230026

Four stereoisomers of a copper-(Schiff-base) complex with double chiral centers were applied to catalyze the asymmetric cyclopropanation. Two of the stereoisomers were also efficient catalysts affording high enantiom... 详细信息

关键词： Asymmetric cyclopropanation copper-(Schiff-base) olefins diazoacetates.

Aerobic Enantioselective Epoxidation of Styrene Analogues Induced by (β-Diketone)-iron( Ⅲ ) Complex

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Chinese Chemical Letters 2005年第11期16卷 1467-1470页

作者： Qing Fang CHENG Xing you XU Wei Xing MA Shu Jie YANG tian pa you Department of Chemical Technology Huaihai Institute of Technology Lianyungang 222005 Meterials Chemistry Laboratory Nanjing University of Science and Technology Nanjing 210094 Department of Chemistry University of Science and Technology of China Hefei 230026

Tris（d,d-dicampholylmethanato） iron （Ⅲ） complex, Fe（dcm）3, was found to be an excellent catalyst for asymmetric oxygenation of styrene analogues into the corresponding epoxides. Good chemical yields and higher enantioselectivity were obtained with combined use of molecular oxygen and an aldehyde at 30℃, Some factors influencing enantioselectivity were discussed.

关键词： Epoxidation oliefin asymmetric catalysis (β-diketone)-iron (Ⅲ) complex.

Catalytic Asymmetric Cyclopropanation using a New Chiral β-Diketone Cu (Ⅱ) Complex as a Catalyst

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Chinese Chemical Letters 1998年第7期9卷 607-608页

作者： Yu XU Zhong Yi WANG and tian pa you(Department of Chemistry, University of Science and Technology of China, Hefei 230026) Department of Chemistry Univ. of Sci./Technology of China Hefei 230026 China

A new chiral β-diketone Cu (Ⅱ) catalyst was synthesized and used for the asymmetric cyclopropanation of styrene with diazoester. A high optical yield (~90%) was achieved. The effect of the structure of substrate on the enantioselectivity was studied. Both chendcal yield and optical yield being reduced when the steric bulky substrate was employed. The reaction mechanism and the chiral model of the transition state are under fufther investigation.

关键词： Asymmetric cyclopropanation β-Diketone Cu (Ⅱ) Complex

Perylene Bisimide In-chain Polyethylene with Unique Self-assembly Nanostructure through Acyclic Diene Metathesis(ADMET)Polymerization

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Chinese Journal of Polymer Science 2018年第6期36卷 703-711页

作者： Wei Song Yang you tian-Jing Li Juan Li Liang Ding Department of Polymer and Composite Material School of Materials EngineeringYancheng Institute of TechnologyYancheng 224051China Roy&Diana Vagelos Laboratories Department of ChemistryUniversity of PennsylvaniaPhiladelphia 19104-6323PAUSA School of Automotive Engineering Yaneheng Vocational Institute of Industry TechnologyYancheng 224005China

A novel perylene tetracarboxylic acid bisimide（PTCBI） in-chain polyethylene（PE） was first prepared via acyclic diene metathesis（ADMET） polymerization of PTCBI-functionalized α,ω-diene monomer. The polymers could spontaneously self-assemble into hollow cylindrical structures in which the π-π interaction between adjacent PTCBI moieties was enhanced and the electron mobility was possibly promoted. The hydrogenation of as-obtained polymer was readily accomplished, affording the desired precision PTCBI in-chain PE with a saturated backbone, which showed high glass transition temperature（Tg = 63 °C）, relatively wide range of light absorption（λ = 200-575 nm）, and higher LUMO level（-3.62 e V）. It can therefore serve as a superior model for facile construction of functional polyolefin and soluble PTCBI polymer with ordered architecture.

关键词： Acyclic diene metathesis polymerization Hydrogenation Polyethylene Perylene bisimide

An Algorithm for Detecting Ice Cloud at Different Altitudes by Combining Dual CrIS Full Spectrum Resolution CO2 Channels

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Journal of Tropical Meteorology 2020年第3期26卷 300-310页

作者： WANG Li-wen ZHENG you-fei tian Miao XU Jing-xin Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science&TechnologyNanjing 210044 China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science&TechnologyNanjing 210044China Information Engineering Department School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengdu 611731 China State Environmental Protection Key Laboratory of Atmospheric Physical Modeling and Pollution Control State Power Environmental Protection Research InstituteNanjing 210031 China

Using infrared sensors to detect ice clouds in different atmospheric layers is still a *** different scattering and absorption properties of longwave and shortwave infrared channels can be utilized to fulfill this *** this study,the release of Suomi-NPP Cross-track Infrared Sounder(Cr IS)full spectrum resolution is used to select and pair channels from longwave(~15μm)and shortwave(~4.3μm)CO2 absorption bands under stricter conditions,so as to better detect ice ***,the differences of the weighting function peaks and cloud insensitive level altitudes of the paired channels are both within 50 h pa so that the variances due to atmospheric conditions can be *** training data of clear sky are determined by Visible Infrared Imaging Radiometer Suite(VIIRS)cloud mask product and used to find the linear relationship between the paired longwave and shortwave CO2 absorption *** the linear relationship,the so-called cloud emission and scattering index(CESI)is derived to detect ice *** clearly captures the center and the ice cloud features of the Super Typhoon Hato located above 415 h ***,the CESI distributions agree with cloud top pressure from the VIIRS in both daytime and nighttime in different atmospheric layers.

关键词： Cross-track Infrared Sounder Full Spectral Resolution(CrIS FSR) ice cloud detection dual CO2 absorption bands

Hydroxyapatite/palmitic acid superhydrophobic composite coating on AZ31 magnesium alloy with both corrosion resistance and bacterial inhibition

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Frontiers of Materials Science 2024年第1期18卷 71-83页

作者： Hang Zhang Shu Cai Huanlin Zhang Lei Ling you Zuo Hao tian Tengfei Meng Guohua Xu Xiaogang Bao Mintao Xue Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education Tianjin UniversityTianjin 300072China Department of Orthopedic Surgery Spine CenterChangzheng HospitalNaval Medical UniversityShanghai 200003China

The coating-modified magnesium(Mg)alloys exhibit controllable corrosion resistance,but the insufficient antibacterial performance limits their clinical applications as degradable *** coatings show excellent performance in terms of both corrosion resistance and inhibition of bacterial adhesion and *** this work,a hydroxyapatite(HA)/palmitic acid(pa)superhydrophobic composite coating was fabricated on the Mg alloy by the hydrothermal technique and immersion *** HA/pa composite coating showed superhydrophobicity with a contact angle of 153°and a sliding angle of 2°.The coated Mg alloy exhibited excellent corrosion resistance in the simulated body fluid,with high polarization resistance(77.10 kΩ·cm^(2))and low corrosion current density((0.491±0.015)μA·cm^(-2)).Meanwhile,the antibacterial efficiency of the composite coating was over 98% against *** and *** in different *** results indicate that the construction of such superhydrophobic composite coating(HA/pa)on the Mg alloy can greatly improve the corrosion resistance of Mg alloy implants within the human body and avoid bacterial infection during the initial stages of implantation.

关键词： superhydrophobic coating hydroxyapatite corrosion resistance antibacterial